Antibacterial Surfaces with Activity against Antimicrobial Resistant Bacterial Pathogens and Endospores

Abstract

Hospital-acquired bacterial infections are a significant burden on healthcare systems worldwide causing increased duration of hospital stays and prolonged patient suffering. We show that polyurethane containing crystal violet (CV) and 3-4 nm zinc oxide nanoparticles (ZnO NPs) possesses excellent bactericidal activity against hospital-acquired pathogens including multidrug resistant Escherichia coli, Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus (MRSA) and even against highly-resistant endospores of Clostridioides (Clostridium) difficile. Importantly, we used clinical isolates of bacterial strains, a protocol to mimic the environmental conditions of a real exposure in the healthcare setting and low light intensity equivalent to that encountered in UK hospitals (~500 lux). Our data shows that ZnO NPs enhance the photobactericidal activity of CV under low intensity light even with short exposure times and we show that this involves both Type I and Type II photochemical pathways. Interestingly, polyurethane containing ZnO NPs alone showed significant bactericidal activity in the dark against one strain of E. coli indicating that the NPs possess both lightactivated synergistic activity with CV and inherent bactericidal activity that is independent of light.These new antibacterial polymers are potentially useful in healthcare faciilties to reduce the transmission of pathogens between people and the environment.

Facile Route to Effective Antimicrobial Aluminum Oxide Layer Realized by Co-Deposition with Silver Nitrate

“…Public attention has focused on indirect spread and transmission of pathogenic microorganisms through surfaces, which require careful disinfection. For example, the common spread of infections caused by viruses and bacteria in healthcare settings [1], combined with the ever-increasing bacterial antibiotic resistance, represent a critical concern, especially for the health of already fragile subjects [2,3]. Moreover, surface contamination in public spaces constitutes a major cause for apprehension: train and metro stations, airports, restaurants, and elevators must be subject to constant disinfection of all touch-on surfaces [4].…”

Opportunities for Nanomedicine in Clostridioides difficile Infection

“…Polyurethane containing crystal violet (CV) and 3–4 nm ZnO nanoparticles have been reported to present bactericidal activity against hospital-acquired pathogens including multidrug-resistant E. coli , Pseudomonas aeruginosa , methicillin-resistant S. aureus (MRSA) and even highly resistant endospores of C. difficile [ 157 ]. However, recent studies showed that ZnO nanoparticles may affect other microorganisms and impact normal intestinal microflora despite their widespread use in biomedicine [ 158 ].…”

Synergistic interactions of cadmium-free quantum dots embedded in a photosensitised polymer surface: efficient killing of multidrug-resistant strains at low ambient light levels

“…Illumination at 500 lux of CVZnO substrates showed comparable antimicrobial effects against E. coli and P. aeruginosa, although the P. aeruginosa strain employed in the study was a laboratory isolate. 47 Another approach using polymer surfaces with antimicrobial activity was undertaken by Boyer et al An antimicrobial polymer consisting of oligoethylene glycol, hydrophobic ethylhexyl, and cationic primary amine groups was effective against P. aeruginosa. However, good bacteriostatic activity was achieved by combining the antimicrobial polymer with the antibiotic doxycycline.…”